Many approaches have attempted to deliver drugs transdermally, including microneedles, topical application of lotions, and iontophoresis. Effective delivery of therapeutic agents through the stratum corneum remains a challenge. While the use of electromotive force to deliver molecules transdermally has provided some level of success, traditional iontophoresis systems typically use equipment, such as external stimulators or other systems, which must be connected to electrodes or other delivery components. The electrodes, and therefore, the user, are tethered to equipment. These systems are particularly inadequate for areas of the body, such as the face, where tethered systems may impede a user's ability and willingness to use a drug delivery system.
In cosmetic applications, individuals typically either use lotions and creams, or resort to needle injections of therapeutic agents. Many individuals find creams less effective, but would prefer not to receive injections. Effective, standalone drug delivery systems are a challenge for these applications due to the need for the system to conform to the therapy site and be sufficiently lightweight, comfortable, and efficacious.